Distinct developmental profiles in typical speech acquisition

Abstract

<jats:p>Three- to five-year-old children produce speech that is characterized by a high level of variability within and across individuals. This variability, which is manifest in speech movements, acoustics, and overt behaviors, can be input to subgroup discovery methods to identify cohesive subgroups of speakers or to reveal distinct developmental pathways or profiles. This investigation characterized three distinct groups of typically developing children and provided normative benchmarks for speech development. These speech development profiles, identified among 63 typically developing preschool-aged speakers (ages 36–59 mo), were derived from the children's performance on multiple measures. These profiles were obtained by submitting to a k-means cluster analysis of 72 measures that composed three levels of speech analysis: behavioral (e.g., task accuracy, percentage of consonants correct), acoustic (e.g., syllable duration, syllable stress), and kinematic (e.g., variability of movements of the upper lip, lower lip, and jaw). Two of the discovered group profiles were distinguished by measures of variability but not by phonemic accuracy; the third group of children was characterized by their relatively low phonemic accuracy but not by an increase in measures of variability. Analyses revealed that of the original 72 measures, 8 key measures were sufficient to best distinguish the 3 profile groups.</jats:p>

Data-Driven Subclassification of Speech Sound Disorders in Preschool Children

“…Specifically, the majority (76%) of sample participants were identified as Group A. A post hoc comparison between the performance profiles of Group A participants and those of a group of typically developing children described previously (Vick et al, 2012) yielded no differences between the groups across the measures reported in this study, except that participants in Group A had more speech sound errors using conversational speech measures, such as the revised percentage of consonants correct. 1 Of particular interest was that, as in children with typical speech acquisition, participants in Group A had typical motor speech skills as measured by speech and nonspeech articulatory kinematic variables.…”

“…The tasks and the rationale for inclusion are described in Table 1. Measures of nonspeech tasks (i.e., chewing and vertical jaw oscillation) were included because these measures were found to be sensitive to differences in developmental subgroupings of preschool children with typical speech (Vick et al, 2012). …”

“…Data were parsed in accordance with a parallel data set from preschool-age children with typical speech acquisition described in a prior report (Vick et al, 2012); the temporal overlap of these analyses reduced potential bias arising from the researcher's knowledge of a participant's diagnosis.…”

Sensibilidade e especificidade da Porcentagem de Consoantes Corretas Revisada na identificação do transtorno fonológico

“…As pointed out before, since its proposal in 1997 (7) the PCC-R index has been applied in different studies with children in order to describe phonological competence and accuracy, as it reflects the speech-language acquisition in the child's linguistic environment (26) . However, there is no age curve that demonstrates phonological development by means of its values.…”

Ocorrência do desvio fonológico e de processos fonológicos em aquisição fonológica típica e atípica

“…Phonological acquisition does not follow a uniform pattern across the population, with some children experiencing delays or deviations in the process (3) . Phoneme substitutions or even deletions, leading to the omission of a phoneme or even an entire syllable from a particular word, are a common part of phonological acquisition (4) . However, over the course of typical development, children will gradually overcome these difficulties and fill out their phonological inventory.…”